A 4,000-word interview with Joya written by Hari appears to pass off a number of quotes and formulations from her book, Raising my Voice, as if they were direct speech from an interview he conducted with her in a London flat.

The similarities, identified by the author of the Islam Versus Europe blog, join a growing list of examples exposed by bloggers where the Orwell prize-winning writer appeared to have inserted quotes into interviews that looked to have come from elsewhere.

The Islam Versus Europe blogger cites 15 examples of duplications in phraseology from the book which Joya published the same year in which Hari subsequently printed the interview.

Hari says he conducted the interview in a London apartment "where she [Joya] is staying with a supporter for a week". But at no stage does Hari indicate that some of the quotes he uses appear to be direct lifts from her book.

Joya was also one of the writers whom Hari cited in his written explanation of his technique.

Hari defended himself by saying he drew a distinction between the "intellectual accuracy of describing [interviewees'] ideas in their most considered words, or the reportorial accuracy of describing their ideas in the words they used on that particular afternoon".

Hari's woes have been exacerbated by an announcement on Thursday by the organisers of the Orwell prize that they are formally investigating whether Hari should be allowed to keep the award for political journalism he won in 2008.

A statement from the Orwell prize council said the seriousness of the allegations against Hari meant they had "no choice but to investigate further".

Hari's position at the Independent is also likely to be more uncertain following the news that editor, Simon Kelner, supposedly Hari's chief protector at the newspaper, is to be become editor-in-chief with the day to day editing taken over by the Evening Standard's city editor, Chris Blackhurst.

On Wednesday Kelner defended Hari on Radio 4's The Media Show claiming the attacks were "politically motivated".

Hari and Kelner had not responded to inquiries at the time of publication.

Examples

Hari interview with Joya

"I realised women's rights had been sold out completely ... Most people in the West have been led to believe that the intolerance and brutality towards women in Afghanistan began with the Taliban regime. But this is a lie".

Joya's book Raising my Voice

"Most people in the West have been led to believe that intolerance, brutality and the severe oppression of women in Afghanistan began with the Taliban regime. But this is a lie..."

Hari's interview

"It turned out my mission," she says, "would be to expose the true nature of the jirga from within."

From Raising my Voice

"My mission would be to expose the true nature of the Jirga from within it"

Hari's interview

For a moment, as these old killers started to give long speeches congratulating themselves on the transition to democracy, Joya felt nervous. But then, she says, "I remembered the oppression we face as women in my country, and my nervousness evaporated, replaced by anger."

In Raising my Voice

"I stood up at the table in front of the room, wondering if my thoughts would be as dry as my mouth. But then I remembered the oppression we face as women in my country, and my nervousness evaporated, replaced by anger."

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